PXR40RM Datasheet, PDF (927/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

RXCTR - RX FIFO counter
POPNXTPTR - Pop Next Pointer
RX FIFO Depth - Receive FIFO depth, implementation specific
Deserial Serial Peripheral Interface (DSPI)
Freescale Semiconductor
PXR40 Microcontroller Reference Manual, Rev. 1
25-67